The present invention relates to a polishing composition used mainly in polishing of polysilicon and to a polishing method using the polishing composition.
In semiconductor device manufacturing processes, for example, polishing may be conducted to remove part of polysilicon film formed on substrates. In this polishing, it is not only desirable to remove polysilicon at high rate, but it is also important to minimize the occurrence of dishing that reduces the flatness of the surface of polished polysilicon film. Dishing refers to a phenomenon in which after part of polysilicon film not to be removed is polished and removed, depressions are formed on the surface of the polished polysilicon film. Many of the previously known polishing compositions cannot be practically used because they do not meet the performance requirements for polysilicon removal rate and dishing sufficiently.
Examples of a document relating to the present invention include Japanese Laid-Open Patent Publication Nos. 2002-190458 and 2005-175498.